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 11-98 transformer
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 Return to top of page · Post #: 16 · Written at 5:07:05 PM on 25 April 2024.
Gandhn's Gravatar
 Location: Cameron Park, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 390

No valves lit up or anything
Did you check the 6 volt winding on the transformer, will be pins 4 and 5 on the 6V4?
Pin 3 is the cathode, if it is open circuit, there will be no HT anywhere, so that may be your only problem.
Harold


 
 Return to top of page · Post #: 17 · Written at 6:34:08 PM on 25 April 2024.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2375

The socket has unused contact tags in it. One of those can be moved to Pin 3. There is no need to replace the whole socket.

Just pick an unused tag, squeeze the tag firmly near the insulator with a pair of long-nose pliers, and push it out the top.
Fit it in place of the damaged one and give the locking tab a stab with a jeweller's screwdriver. Then solder its wire back on.

Old servicing trick!


 
 Return to top of page · Post #: 18 · Written at 4:27:41 PM on 3 May 2024.
Gandhn's Gravatar
 Location: Cameron Park, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 390

Your question prompted a fair bit of discussion, how did you get on?
Was the transformer OK and were you able to fix the rectifier socket?
Harold


 
 Return to top of page · Post #: 19 · Written at 8:07:31 PM on 3 May 2024.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5266

You can if the socket is a write off, drill out rivets. However, anything like that I prefer to do with the tubes out. If you are going to buy in a new socket, I prefer Ceramic ones on rectifiers & output tubes as most damage to the Bakelite fibre ones is caused by heat, tracking and overloads.

I would concur with Harold: One does like to see operational dial lights & heaters. A faulty AWA dial light socket was reported recently and I had one of the same do the same thing. This does not come under unusual faults, I have also had a HMV / Marconi and a Breville, Kriesler plastic, and a 5Y3 with socket and wiring shorts.

Marc


 
 Return to top of page · Post #: 20 · Written at 11:55:57 AM on 12 May 2024.
Ehsuz's Gravatar
 Location: Newcastle, NSW
 Member since 6 June 2020
 Member #: 2422
 Postcount: 5

Hi All,
Sorry been in hospital. Not electrocuted some mystery rheumatoid thingy.
I replaced the socket. Easy enough to do
Still no lights, but I haven't checked the globe.
I have 280 volts on pin 1 and pin 7 on 6V4 so that part of the transformer is ok.
I had a spare 6V4 but the readings are the same for both.

Pin 4 drops from 3.7 down to .7 quickly and stays there.
There is no power on any of the other test points.


 
 Return to top of page · Post #: 21 · Written at 2:25:51 PM on 12 May 2024.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6692

Pin 4 drops from 3.7 down to .7 quickly and stays there.

6.3 volt winding or heater circuit shorted? Is the transformer humming and/or getting hot?

There is no power on any of the other test points.

Do you mean other valve heater connection points?


 
 Return to top of page · Post #: 22 · Written at 9:23:23 AM on 18 May 2024.
Ehsuz's Gravatar
 Location: Newcastle, NSW
 Member since 6 June 2020
 Member #: 2422
 Postcount: 5

So there is no power at the light socket
is that where I should get 6 volts?
Thanks all


 
 Return to top of page · Post #: 23 · Written at 9:50:55 AM on 18 May 2024.
Gandhn's Gravatar
 Location: Cameron Park, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 390

Yes, you should see 6V at the dial lamp.
Can you go back to where the 6V winding wires come out of the transformer and see if there is voltage there? If not, then unsolder the 6V lead and see if there is voltage at the transformer. If yes, there is either a short or a break in the wiring. If no, and you are getting the high voltage correctly, then the transformer is suspect.
You didn't, by chance, have your meter on DC volts?
Harold


 
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